1. Field of the Invention
The present invention relates to an amplifier, and more particularly to an amplifier that can be connected to a plurality of content reproducing devices.
2. Description of the Related Art
In recent years, amplifiers such as an AV amplifier and an AV receiver have come into wide use. Referring to FIG. 8, a AV receiver 100 is connected to a DVD player AVP1 and a CD player AVP2, which are content reproducing devices AVP. The AV receiver 100 is also connected to a plurality of speakers SP (SP1 and SP2). The AV receiver 100 performs a predetermined signal processing operation on an audio signal from a content reproducing device AVP, and outputs the processed signal to a speaker SP. Thus, the user can enjoy high-quality sound.
The user can operate an intended content reproducing device AVP via the AV receiver 100.
For example, where the AV receiver 100, the DVD player AVP1 and the CD player AVP2 are installed in a room Zone1, if the user in another room Zone2 wishes to operate the DVD player AVP1, the user uses a remote controller RC2 to transmit an control command to a remote controller receiver RE2. Then, the AV receiver 100 receives the control command via the remote controller receiver RE2, and transmits an control command to the DVD player AVP1 selected by the user. When the DVD player AVP1 outputs an audio signal based on the control command, the AV receiver 100 performs a signal processing operation on the audio signal, and outputs the processed signal to the speaker SP2 installed in the room Zone2. Through the operation described above, the user can operate the content reproducing devices AVP via the AV receiver 100.
With such a system, however, a plurality of users cannot simultaneously operate a plurality of content reproducing devices AVP via the AV receiver 100. For example, while a user is operating the DVD player AVP1 in the room Zone2, another user in the room Zone1 cannot operate the CD player AVP2 via the AV receiver 100.